I experimented with cholla, which when alive is a cactus but when dead is a gorgeous piece of hard hard wood with many holes in it which gives smaller fish a place to hide. Also the pleco's love it as a chew toy sort of speak. I washed mine and soaked it for a few days to water log it as it floats if you don't. It released a small amount of tanins which ever so slightly tinged the water brown, but after a water change it was clear as a bell..I too am in the states and my father brought this back to me from new mexico..I have tons left over if your interested I would sell for cheap.. let me know. Here is a pic of how it looked in this tank